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InP-Based Quantum Dots as Photosensitizers in Photodynamic Antimicrobial Materials.
Lihan Chen1, Chenyu Jiang2, Frank Scholle3
1Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, United States.
ACS Applied Bio Materials
|January 17, 2025
Summary
Nontoxic, ligand-functionalized indium phosphide (InP)-based quantum dots (QDs) show promise for self-sterilizing surfaces. These quantum dots effectively inactivate bacteria and viruses via photodynamic action, offering a new approach to preventing pathogen transmission.
Area of Science:
- Materials Science
- Nanotechnology
- Photochemistry
Background:
- Pathogen transmission via high-contact surfaces poses a significant public health risk.
- Traditional antimicrobial strategies face challenges with resistance and toxicity.
- Quantum dots (QDs) offer tunable optical properties for novel applications.
Purpose of the Study:
- To develop and evaluate nontoxic, ligand-functionalized InP-based quantum dots (QDs) as photosensitizers for antimicrobial applications.
- To assess the efficacy of QD-functionalized materials in inactivating various bacteria and viruses.
- To investigate the potential of these materials for creating self-sterilizing surfaces.
Main Methods:
- Synthesis of core/shell InP/ZnSe/ZnS QDs via hot injection method, followed by ligand exchange with 9-anthracene carboxylic acid (ACA).
- Characterization of QD size (TEM) and optical properties (absorption/emission spectra).
- Application of QDs to cellulose via dip coating and assessment of antimicrobial photodynamic inactivation (aPDI) under visible light illumination.
- Evaluation of antiviral activity and cytotoxicity on mammalian cells.
Main Results:
- Synthesized InP/ZnSe/ZnS QDs exhibited uniform size (∼3.2 nm) and broad visible light absorption (λmax ∼550 nm).
- QD-ACA conjugates efficiently generated singlet oxygen (¹O₂) via a type II photodynamic mechanism.
- QD-loaded cellulose demonstrated high antimicrobial efficacy, achieving >5 log reduction for MRSA and complete inactivation of VRE, MDRAB, and KP.
- Complete inactivation of human coronavirus 229E (HCoV-229E) and feline calicivirus (FCV) was achieved.
- QDs exhibited no significant cytotoxicity to mammalian cells in the dark.
Conclusions:
- Ligand-functionalized InP-based QDs are effective nontoxic photosensitizers for antimicrobial photodynamic inactivation.
- QD-functionalized materials show significant potential for developing self-sterilizing surfaces to combat pathogen transmission.
- This technology offers a promising alternative to conventional antimicrobial methods.
